Wire-gage.



A. W. ROBERTSON.

WIRE GAGE.

APPLICATION FILED SEPT. 7. 1912.

1,121,289, Patented Dec. 15,1914.

THE NORRIS PETERS c0. PHOTOLITHO WASHINGTON u. c

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ARTHUR \V. ROBERTQ'CN, OF CHICAGO, ILLINOIS, ASSIGNOR OF ONE-THIRD TO 'W'ILLIAIK L. RCBERTSON, O51 LEADVILLE, COLORADO, AND ONE-THIRD TO JOHN H. ROBERTSON, 0F PLATTEVILLE, -WISCONSUV.

TIRE-GAGE;

Specification of Letters Patent.

Patented Dec. 15, 1914.

Application filed September 7, 1912. Serial No. 719,230.

T 0 all rv/10mit may concern Be it known that I, ARTHUR W. ROBERT- SON, a citizen of the United States of America, and a resident of Chicago, county of Cook, and State of Illinois, have invented certain new and useful Improvements in Wire-Gages, of which the following is a specification.

The main objects of this invention are to provide an improved form of wire gage, especially one which may be in the form of an ordinary jack knife and thus serve as a convenient Combination tool which a workman may always have at hand.

These objects are accomplished by the device shown in the accom an in drawin s in which:

Figure 1 is a side view of a combined wire gage, jack knife, and screw starting awl, embodying this invention, and illustrating the parts in position for use as a wire gage. Fig. 2 is a view of a knife wire gage showing the indicator blade in extended position for use as an awl or gimlet.

In the form shownrin the drawings the device comprises the sheath or handle 1 which has pivotally mounted therein at one end a knife blade 2, and at the other end a narrower pointed blade 3, suitable for use as an awl for making holes in wood etc., for starting screws and the like. The large blade 2 has a graduated scale 4 etched 0r engraved on one side, the graduations being numbered to correspond with the most common sizes of wire used in electrical construction work, and being arranged as will be hereinafter described. Extending along the inner edge of the handle is a series of transversely disposed notches or grooves 5 of various sizes, each being designed to receive a wire of respectively different size. The notch accommodating the largest wire is nearest the pivot of the knife blade, and each successive notch is of relatively smaller size than its predecessor. Each of the notches is numbered to correspond to the size of the wire for which it is intended.

The large blade 2 has a flattened shoulder 9 which coacts with the spring 10 to hold the blade 2 in the position which it occupies in Fig. 1, being the position to which it is set when the device is to be used as a wire gage. The narrow blade 3 has a pointed end 6 and is adapted, when closed against which the respective notch is intended. If.

the wire is of the gage corresponding to the number adjacent to the notch in which it is seated, then the pointed end 6 of the blade 3 will point to a graduation on the scale at of like number. If it does not point to this graduation it is necessary for the user to test the wire in a different notch.

It is, of course, understood that a workman constantly using wires of diiferent sizes is able to tell at a glance approximately the gage of a piece of wire, and usually he will be able to place the wire in its proper notch at the first or second trial. This type of wire gage is important on account of the fact that it may form a part of the knife used by electricians for stripping the insulation from electric wires, and for the other uses to which such knives are applied. It is not intended to take the place altogether of other forms of wire gages, but is intended to enable a workman to decide quickly which of two or three sizes is the correct size of wire when there is uncertainty. For ordinary wiring it takes the place of both knife and gage, and makes it unnecessary for the workman to carry a separate gage.

Although but one specific embodiment of this invention has been herein shown and described, it will be understood that numerous details of the construction shown may be altered or omitted without departing from the spirit of this invention as defined by the following claims.

I claim:

1. A wire gage comprising a member having therein a series of transverse notches, a second member pivoted thereto and adapted to be swung into engagement with a wire seated in one of said notches, and a third member having graduations thereon adapted to coact with said second member for identifying the gage of such wire.

2, A wire gage, comprising a member notched to engage a wire, a second member pivotally mounted on said notched member and movable relatively to said notched member to coact therewith in gaging a wire, and a graduated member connected to one of said other members and adapted to c0- a pair of blades pivoted thereto at opposite ends said handle having a transverse notch in one edge, one of said blades being adapted to be turned to a position for engaging a Wire: seated in said notch, and the other blade having thereon graduations adapted when said other blade is turned to a certain position to register With said first blade for indicating the gage of the Wire in said notch.

5. A device of the class described com- Gopies of-this patent may be obtained for prising a sheath handle open at one edge,

and having pivotally mounted thereon at opposite ends a pair of blades adapted to be folded into said'sheath springs coacting With said blades, one of said blades having a portion of its edge flattened and adapted to coact with its respective spring for holdingit in a certain partly open position, said blade having thereon a graduated scale said sheath being provided With a series of transverse notches between said blades, and said other blade ,beingadapted to be turned to engage a Wire seated in one of said notches and to coact With said scale for gaging such Wire.

Signedat Chicago this 31st day of Au gust 1912. I V ARTHUR W. ROBERTSON.

Witnesses EUGENE A. RUMMLER, CHARLES S. "COLE.

five cents each, by addressing the Commissioner of Patents, Washington, D. Q. a 

